>perl -MDevel::Peek -e"my $x = {}; Dump($x);"
SV = IV(0x3269b8) at 0x3269c0
  REFCNT = 1
  FLAGS = (PADMY,ROK)
  ...

>perl -MDevel::Peek -e"my $x = 'abc'; $x = {}; Dump($x);"
SV = PV(0x33abe0) at 0x2a69d0
  REFCNT = 1
  FLAGS = (PADMY,ROK)
  ...

>perl -MDevel::Peek -e"my $x = 'abc'; $x = 123; $x = {}; Dump($x);"
SV = PVIV(0x28da78) at 0x2a6a60
  REFCNT = 1
  FLAGS = (PADMY,ROK)
  ...